A generic internal combustion piston engine of the pre-cited type is known from U.S. Pat. No. 3,809,033. An actuating piston installed in the rocker arm of this engine is operatively connected to a bridge associated to two exhaust valves. The pressure chamber of the actuating piston is controlled by a control valve, so that oil pressure can be increased and decreased and the actuating piston can be retracted for the performance operation of the internal combustion engine or extended for the braking operation. The additional cam is active in the one case and inactive in the other.
A drawback of this configuration is particularly that, due to the spatial arrangement in the rocker arm, it is only possible to open all the exhaust valves intermediately at the same time, and this is only restrictedly desired. Furthermore, this also makes the installation of a hydraulic lash adjusting element for simplifying maintenance of the internal combustion engine more difficult.
Further, an internal combustion piston engine comprising a compression relief brake device is also known (DE-30 03 566 A1). In this internal combustion engine, the additional cam is configured as a movable component that can be pushed into the base circle contour or pushed outwards out of the base circle contour. For this purpose, the camshaft has a hollow configuration and comprises an actuating device which displaces the additional cam. The actuating device must further also comprise actuating elements outside of the camshaft, through which actuating elements the inner actuating device is controlled.
The required structural complexity for extending and retracting the additional cams is considerably high and cost-intensive and therefore considered as a drawback.